Nucleosomes are not necessary for promoter-proximal pausing in vitro on the Drosophila hsp70 promoter.
RNA polymerase II has been found to pause stably on several metazoan genes in a promoter-proximal region located 20-40 nt downstream from the start site of transcription. Escape of polymerase from this paused state has been proposed to be a rate limiting step in transcription of some genes. A study of the human hsp70 promoter showed that a nucleosome positioned downstream from the transcription start was a key component in establishing a stably paused polymerase in one cell-free system. We tested whether these results could be extended to the Drosophila hsp70 promoter in a Drosophila cell-free system and found that polymerase paused stably on the promoter even when the length of DNA downstream from the transcription start was not sufficient for assembly of a nucleosome. Our results indicate that a downstream nucleosome is not a universal requirement for stably pausing RNA polymerase in the promoter-proximal region.
Benjamin
L R
LR
Center for Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA.
Gilmour
D S
DS
D000818:Animals; D001483:Base Sequence; D002474:Cell-Free System; D004247:DNA / Q000235:genetics / Q000378:metabolism; D017931:DNA Primers / Q000235:genetics; D004330:Drosophila / Q000235:genetics* / Q000378:metabolism; D017344:Genes, Insect; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics*; D006801:Humans; D019476:Insect Proteins / Q000235:genetics; D007700:Kinetics; D009707:Nucleosomes / Q000235:genetics* / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D012319:RNA Polymerase II / Q000378:metabolism; D014158:Transcription, Genetic
D017931:DNA Primers; D018840:HSP70 Heat-Shock Proteins; D019476:Insect Proteins; D009707:Nucleosomes; D004247:DNA; D012319:RNA Polymerase II